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101.
人重组白蛋白基因在巴斯德毕赤酵母中的高效表达 总被引:10,自引:0,他引:10
The yeast Pichia pastoris was transformed by the multi\|copy Pichia expression vector that can express secreted human albumin.The high level expression of cell line was selected after screening.The expression of human recombinant albumin in Pichia pastoris induced by different methods were compared.The retio of secreted human albumin is 80% in total secreted proteins and the expression level reaches as high as is 10g/L. 相似文献
102.
Mengjiao Zhu Lijie Han Ya Lv Yishan Liu Pan Li Haichun Jing Hongwei Cai 《植物学报(英文版)》2018,60(10):938-955
Tillering contributes to grain yield and plant architecture and therefore is an agronomically important trait in sorghum (Sorghum bicolor). Here, we identified and functionally characterized a mutant of the Non‐dormant Axillary Bud 1 (NAB1) gene from an ethyl methanesulfonate‐mutagenized sorghum population. The nab1 mutants have increased tillering and reduced plant height. Map‐based cloning revealed that NAB1 encodes a carotenoid‐cleavage dioxygenase 7 (CCD7) orthologous to rice (Oryza sativa) HIGH‐TILLERING DWARF1/DWARF17 and Arabidopsis thaliana MORE AXILLARY BRANCHING 3. NAB1 is primarily expressed in axillary nodes and tiller bases and NAB1 localizes to chloroplasts. The nab1 mutation causes outgrowth of basal axillary buds; removing these non‐dormant basal axillary buds restored the wild‐type phenotype. The tillering of nab1 plants was completely suppressed by exogenous application of the synthetic strigolactone analog GR24. Moreover, the nab1 plants had no detectable strigolactones and displayed stronger polar auxin transport than wild‐type plants. Finally, RNA‐seq showed that the expression of genes involved in multiple processes, including auxin‐related genes, was significantly altered in nab1. These results suggest that NAB1 functions in strigolactone biosynthesis and the regulation of shoot branching via an interaction with auxin transport. 相似文献
103.
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105.
人源性抗HBsAg Fab抗体的发酵生产研究 总被引:3,自引:0,他引:3
为了适应工业生产的需要,利用fed—batch方法,重组人源性抗HBsAg Fab抗体酵母工程菌在30L发酵罐中进行了高密度发酵,发酵最适温度30℃,pH值范围5.0~5.3,溶氧范围20%~30%。发酵液OD600值达到300时开始诱导,甲醇最佳诱导浓度为10mL/L。重组人源性抗HBsAg Fab抗体经离子交换层析纯化,纯化产品经SDS-PAGE、Western blot进行分析和ELISA方法进行活性测定。结果显示,重组Fab抗体在Fed-batch发酵系统中可高效表达,经过192h的发酵生产,重组人源性抗HBsAg Fab抗体的表达量可达412mg/L。发酵上清经过离子交换层析纯化,获得纯度为95%的重组Fab抗体,该Fab抗体经ELISA分析具有较高的HBsAg抗原亲和力和特异性。结果证实可以通过高密度发酵毕赤酵母工程菌来高效生产重组人源性抗HBsAg Fab抗体,为后续的工业化生产应用奠定了基础。 相似文献
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107.
Knowledge of protein-protein interactions (PPIs) plays an important role in constructing protein interaction networks and understanding the general machineries of biological systems. In this study, a new method is proposed to predict PPIs using a comprehensive set of 930 features based only on sequence information, these features measure the interactions between residues a certain distant apart in the protein sequences from different aspects. To achieve better performance, the principal component analysis (PCA) is first employed to obtain an optimized feature subset. Then, the resulting 67-dimensional feature vectors are fed to Support Vector Machine (SVM). Experimental results on Drosophila melanogaster and Helicobater pylori datasets show that our method is very promising to predict PPIs and may at least be a useful supplement tool to existing methods. 相似文献
108.
Myokine IL-15 regulates the crosstalk of co-cultured porcine skeletal muscle satellite cells and preadipocytes 总被引:1,自引:0,他引:1
Yinghui Li Fengna Li Binbin Lin Xiangfeng Kong Yulong Tang Yulong Yin 《Molecular biology reports》2014,41(11):7543-7553
The present study was carried out to preliminarily reveal the underlying mechanisms of the co-culture system between porcine muscle satellite cells (SCs) and stromal-vascular cells (SVs). The two cell types were co-cultured to assess both proliferation and differentiation. Desmin and Pref-1 immunofluorescence staining technique were taken to identify the two types of isolated cells. The expression of specific marker genes Myogenin was up-regulated in SCs (P < 0.05) and the differentiation of SCs could be promoted when co-cultured with preadipocytes compared with the single-cultured control, while expression of c/EBPβ in SVs was down-regulated (P < 0.05) and the differentiation of preadipocytes could be inhibited. Furthermore, secretion of myokine IL-15 was markedly increased, as well as its gene and protein expression levels in co-culture supernatants. However, the secretion of adipokine leptin was significantly decreased. These findings demonstrate that myokines like IL-15 could facilitate the SCs’ differentiation while inhibit the SVs differentiation, and act as an important regulator of co-culture between muscle cells and adipocytes. 相似文献
109.
Lv K Guo Y Zhang Y Wang K Jia Y Sun S 《Biochemical and biophysical research communications》2008,374(1):101-105
The biological mechanism of a recent discovered association of type 2 diabetes with the ACAA-insertion/deletion polymorphism at the 3′UTR of the IGF2R gene has remained unclear. A very recently emerging novel polymorphic control layer by microRNAs (miRNAs) makes it possible to elucidate this issue. In this study, a prediction by web tools MicroInspector and miRanda demonstrated that DNA sequence polymorphism (DSPs) ACAA-insertion/deletion in IGF2R 3′UTR is located within the hsa-miR-657 and hsa-miR-453 binding sites. And luciferase reporter assay revealed that hsa-miR-657 acts directly at the 3′UTR of the IGF2R. Furthermore, ACAA-deletion exerted a further repression compared with ACAA-insertion, indicating that hsa-miR-657 regulates IGF2R gene expression in a polymorphic control manner. Importantly, we also demonstrated that hsa-miR-657 can translationally regulate the IGF2R expression levels in Hep G2 cells. Thus, our findings testify the possibility that the ACAA-insertion/deletion polymorphism may result in the change of IGF2R expression levels at least in part by hsa-miR-657-mediated regulation, contributing to the elucidation for the pathogenesis of type 2 diabetes and raise the possibility that miRNAs or in combination with functional DNA sequence polymorphism may be valuable in the treatment of human type 2 diabetes. 相似文献
110.